ReactOS 0.4.15-dev-5666-gc548b97
t1parse.c
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1/***************************************************************************/
2/* */
3/* t1parse.c */
4/* */
5/* Type 1 parser (body). */
6/* */
7/* Copyright 1996-2018 by */
8/* David Turner, Robert Wilhelm, and Werner Lemberg. */
9/* */
10/* This file is part of the FreeType project, and may only be used, */
11/* modified, and distributed under the terms of the FreeType project */
12/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
13/* this file you indicate that you have read the license and */
14/* understand and accept it fully. */
15/* */
16/***************************************************************************/
17
18
19 /*************************************************************************/
20 /* */
21 /* The Type 1 parser is in charge of the following: */
22 /* */
23 /* - provide an implementation of a growing sequence of objects called */
24 /* a `T1_Table' (used to build various tables needed by the loader). */
25 /* */
26 /* - opening .pfb and .pfa files to extract their top-level and private */
27 /* dictionaries. */
28 /* */
29 /* - read numbers, arrays & strings from any dictionary. */
30 /* */
31 /* See `t1load.c' to see how data is loaded from the font file. */
32 /* */
33 /*************************************************************************/
34
35
36#include <ft2build.h>
37#include FT_INTERNAL_DEBUG_H
38#include FT_INTERNAL_STREAM_H
39#include FT_INTERNAL_POSTSCRIPT_AUX_H
40
41#include "t1parse.h"
42
43#include "t1errors.h"
44
45
46 /*************************************************************************/
47 /* */
48 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */
49 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
50 /* messages during execution. */
51 /* */
52#undef FT_COMPONENT
53#define FT_COMPONENT trace_t1parse
54
55
56 /*************************************************************************/
57 /*************************************************************************/
58 /*************************************************************************/
59 /***** *****/
60 /***** INPUT STREAM PARSER *****/
61 /***** *****/
62 /*************************************************************************/
63 /*************************************************************************/
64 /*************************************************************************/
65
66
67 /* see Adobe Technical Note 5040.Download_Fonts.pdf */
68
69 static FT_Error
71 FT_UShort *atag,
72 FT_ULong *asize )
73 {
77
78
79 *atag = 0;
80 *asize = 0;
81
82 if ( !FT_READ_USHORT( tag ) )
83 {
84 if ( tag == 0x8001U || tag == 0x8002U )
85 {
86 if ( !FT_READ_ULONG_LE( size ) )
87 *asize = size;
88 }
89
90 *atag = tag;
91 }
92
93 return error;
94 }
95
96
97 static FT_Error
99 const char* header_string,
100 size_t header_length )
101 {
105
106
107 if ( FT_STREAM_SEEK( 0 ) )
108 goto Exit;
109
111 if ( error )
112 goto Exit;
113
114 /* We assume that the first segment in a PFB is always encoded as */
115 /* text. This might be wrong (and the specification doesn't insist */
116 /* on that), but we have never seen a counterexample. */
117 if ( tag != 0x8001U && FT_STREAM_SEEK( 0 ) )
118 goto Exit;
119
120 if ( !FT_FRAME_ENTER( header_length ) )
121 {
123
124 if ( ft_memcmp( stream->cursor, header_string, header_length ) != 0 )
125 error = FT_THROW( Unknown_File_Format );
126
128 }
129
130 Exit:
131 return error;
132 }
133
134
139 PSAux_Service psaux )
140 {
144
145
146 psaux->ps_parser_funcs->init( &parser->root, NULL, NULL, memory );
147
148 parser->stream = stream;
149 parser->base_len = 0;
150 parser->base_dict = NULL;
151 parser->private_len = 0;
152 parser->private_dict = NULL;
153 parser->in_pfb = 0;
154 parser->in_memory = 0;
155 parser->single_block = 0;
156
157 /* check the header format */
158 error = check_type1_format( stream, "%!PS-AdobeFont", 14 );
159 if ( error )
160 {
161 if ( FT_ERR_NEQ( error, Unknown_File_Format ) )
162 goto Exit;
163
164 error = check_type1_format( stream, "%!FontType", 10 );
165 if ( error )
166 {
167 FT_TRACE2(( " not a Type 1 font\n" ));
168 goto Exit;
169 }
170 }
171
172 /******************************************************************/
173 /* */
174 /* Here a short summary of what is going on: */
175 /* */
176 /* When creating a new Type 1 parser, we try to locate and load */
177 /* the base dictionary if this is possible (i.e., for PFB */
178 /* files). Otherwise, we load the whole font into memory. */
179 /* */
180 /* When `loading' the base dictionary, we only setup pointers */
181 /* in the case of a memory-based stream. Otherwise, we */
182 /* allocate and load the base dictionary in it. */
183 /* */
184 /* parser->in_pfb is set if we are in a binary (`.pfb') font. */
185 /* parser->in_memory is set if we have a memory stream. */
186 /* */
187
188 /* try to compute the size of the base dictionary; */
189 /* look for a Postscript binary file tag, i.e., 0x8001 */
190 if ( FT_STREAM_SEEK( 0L ) )
191 goto Exit;
192
194 if ( error )
195 goto Exit;
196
197 if ( tag != 0x8001U )
198 {
199 /* assume that this is a PFA file for now; an error will */
200 /* be produced later when more things are checked */
201 if ( FT_STREAM_SEEK( 0L ) )
202 goto Exit;
203 size = stream->size;
204 }
205 else
206 parser->in_pfb = 1;
207
208 /* now, try to load `size' bytes of the `base' dictionary we */
209 /* found previously */
210
211 /* if it is a memory-based resource, set up pointers */
212 if ( !stream->read )
213 {
214 parser->base_dict = (FT_Byte*)stream->base + stream->pos;
215 parser->base_len = size;
216 parser->in_memory = 1;
217
218 /* check that the `size' field is valid */
219 if ( FT_STREAM_SKIP( size ) )
220 goto Exit;
221 }
222 else
223 {
224 /* read segment in memory -- this is clumsy, but so does the format */
225 if ( FT_ALLOC( parser->base_dict, size ) ||
226 FT_STREAM_READ( parser->base_dict, size ) )
227 goto Exit;
228 parser->base_len = size;
229 }
230
231 parser->root.base = parser->base_dict;
232 parser->root.cursor = parser->base_dict;
233 parser->root.limit = parser->root.cursor + parser->base_len;
234
235 Exit:
236 if ( error && !parser->in_memory )
237 FT_FREE( parser->base_dict );
238
239 return error;
240 }
241
242
243 FT_LOCAL_DEF( void )
245 {
246 FT_Memory memory = parser->root.memory;
247
248
249 /* always free the private dictionary */
250 FT_FREE( parser->private_dict );
251
252 /* free the base dictionary only when we have a disk stream */
253 if ( !parser->in_memory )
254 FT_FREE( parser->base_dict );
255
256 parser->root.funcs.done( &parser->root );
257 }
258
259
262 PSAux_Service psaux )
263 {
264 FT_Stream stream = parser->stream;
265 FT_Memory memory = parser->root.memory;
268
269
270 if ( parser->in_pfb )
271 {
272 /* in the case of the PFB format, the private dictionary can be */
273 /* made of several segments. We thus first read the number of */
274 /* segments to compute the total size of the private dictionary */
275 /* then re-read them into memory. */
276 FT_ULong start_pos = FT_STREAM_POS();
278
279
280 parser->private_len = 0;
281 for (;;)
282 {
284 if ( error )
285 goto Fail;
286
287 if ( tag != 0x8002U )
288 break;
289
290 parser->private_len += size;
291
292 if ( FT_STREAM_SKIP( size ) )
293 goto Fail;
294 }
295
296 /* Check that we have a private dictionary there */
297 /* and allocate private dictionary buffer */
298 if ( parser->private_len == 0 )
299 {
300 FT_ERROR(( "T1_Get_Private_Dict:"
301 " invalid private dictionary section\n" ));
302 error = FT_THROW( Invalid_File_Format );
303 goto Fail;
304 }
305
306 if ( FT_STREAM_SEEK( start_pos ) ||
307 FT_ALLOC( parser->private_dict, parser->private_len ) )
308 goto Fail;
309
310 parser->private_len = 0;
311 for (;;)
312 {
314 if ( error || tag != 0x8002U )
315 {
317 break;
318 }
319
320 if ( FT_STREAM_READ( parser->private_dict + parser->private_len,
321 size ) )
322 goto Fail;
323
324 parser->private_len += size;
325 }
326 }
327 else
328 {
329 /* We have already `loaded' the whole PFA font file into memory; */
330 /* if this is a memory resource, allocate a new block to hold */
331 /* the private dict. Otherwise, simply overwrite into the base */
332 /* dictionary block in the heap. */
333
334 /* first of all, look at the `eexec' keyword */
335 FT_Byte* cur = parser->base_dict;
336 FT_Byte* limit = cur + parser->base_len;
337 FT_Pointer pos_lf;
338 FT_Bool test_cr;
339
340
341 Again:
342 for (;;)
343 {
344 if ( cur[0] == 'e' &&
345 cur + 9 < limit ) /* 9 = 5 letters for `eexec' + */
346 /* whitespace + 4 chars */
347 {
348 if ( cur[1] == 'e' &&
349 cur[2] == 'x' &&
350 cur[3] == 'e' &&
351 cur[4] == 'c' )
352 break;
353 }
354 cur++;
355 if ( cur >= limit )
356 {
357 FT_ERROR(( "T1_Get_Private_Dict:"
358 " could not find `eexec' keyword\n" ));
359 error = FT_THROW( Invalid_File_Format );
360 goto Exit;
361 }
362 }
363
364 /* check whether `eexec' was real -- it could be in a comment */
365 /* or string (as e.g. in u003043t.gsf from ghostscript) */
366
367 parser->root.cursor = parser->base_dict;
368 /* set limit to `eexec' + whitespace + 4 characters */
369 parser->root.limit = cur + 10;
370
371 cur = parser->root.cursor;
372 limit = parser->root.limit;
373
374 while ( cur < limit )
375 {
376 if ( cur[0] == 'e' &&
377 cur + 5 < limit )
378 {
379 if ( cur[1] == 'e' &&
380 cur[2] == 'x' &&
381 cur[3] == 'e' &&
382 cur[4] == 'c' )
383 goto Found;
384 }
385
387 if ( parser->root.error )
388 break;
390 cur = parser->root.cursor;
391 }
392
393 /* we haven't found the correct `eexec'; go back and continue */
394 /* searching */
395
396 cur = limit;
397 limit = parser->base_dict + parser->base_len;
398
399 if ( cur >= limit )
400 {
401 FT_ERROR(( "T1_Get_Private_Dict:"
402 " premature end in private dictionary\n" ));
403 error = FT_THROW( Invalid_File_Format );
404 goto Exit;
405 }
406
407 goto Again;
408
409 /* now determine where to write the _encrypted_ binary private */
410 /* dictionary. We overwrite the base dictionary for disk-based */
411 /* resources and allocate a new block otherwise */
412
413 Found:
414 parser->root.limit = parser->base_dict + parser->base_len;
415
417 cur = parser->root.cursor;
418 limit = parser->root.limit;
419
420 /* According to the Type 1 spec, the first cipher byte must not be */
421 /* an ASCII whitespace character code (blank, tab, carriage return */
422 /* or line feed). We have seen Type 1 fonts with two line feed */
423 /* characters... So skip now all whitespace character codes. */
424 /* */
425 /* On the other hand, Adobe's Type 1 parser handles fonts just */
426 /* fine that are violating this limitation, so we add a heuristic */
427 /* test to stop at \r only if it is not used for EOL. */
428
429 pos_lf = ft_memchr( cur, '\n', (size_t)( limit - cur ) );
430 test_cr = FT_BOOL( !pos_lf ||
431 pos_lf > ft_memchr( cur,
432 '\r',
433 (size_t)( limit - cur ) ) );
434
435 while ( cur < limit &&
436 ( *cur == ' ' ||
437 *cur == '\t' ||
438 (test_cr && *cur == '\r' ) ||
439 *cur == '\n' ) )
440 cur++;
441 if ( cur >= limit )
442 {
443 FT_ERROR(( "T1_Get_Private_Dict:"
444 " `eexec' not properly terminated\n" ));
445 error = FT_THROW( Invalid_File_Format );
446 goto Exit;
447 }
448
449 size = parser->base_len - (FT_ULong)( cur - parser->base_dict );
450
451 if ( parser->in_memory )
452 {
453 /* note that we allocate one more byte to put a terminating `0' */
454 if ( FT_ALLOC( parser->private_dict, size + 1 ) )
455 goto Fail;
456 parser->private_len = size;
457 }
458 else
459 {
460 parser->single_block = 1;
461 parser->private_dict = parser->base_dict;
462 parser->private_len = size;
463 parser->base_dict = NULL;
464 parser->base_len = 0;
465 }
466
467 /* now determine whether the private dictionary is encoded in binary */
468 /* or hexadecimal ASCII format -- decode it accordingly */
469
470 /* we need to access the next 4 bytes (after the final whitespace */
471 /* following the `eexec' keyword); if they all are hexadecimal */
472 /* digits, then we have a case of ASCII storage */
473
474 if ( cur + 3 < limit &&
475 ft_isxdigit( cur[0] ) && ft_isxdigit( cur[1] ) &&
476 ft_isxdigit( cur[2] ) && ft_isxdigit( cur[3] ) )
477 {
478 /* ASCII hexadecimal encoding */
480
481
482 parser->root.cursor = cur;
483 (void)psaux->ps_parser_funcs->to_bytes( &parser->root,
484 parser->private_dict,
485 parser->private_len,
486 &len,
487 0 );
488 parser->private_len = len;
489
490 /* put a safeguard */
491 parser->private_dict[len] = '\0';
492 }
493 else
494 /* binary encoding -- copy the private dict */
495 FT_MEM_MOVE( parser->private_dict, cur, size );
496 }
497
498 /* we now decrypt the encoded binary private dictionary */
499 psaux->t1_decrypt( parser->private_dict, parser->private_len, 55665U );
500
501 if ( parser->private_len < 4 )
502 {
503 FT_ERROR(( "T1_Get_Private_Dict:"
504 " invalid private dictionary section\n" ));
505 error = FT_THROW( Invalid_File_Format );
506 goto Fail;
507 }
508
509 /* replace the four random bytes at the beginning with whitespace */
510 parser->private_dict[0] = ' ';
511 parser->private_dict[1] = ' ';
512 parser->private_dict[2] = ' ';
513 parser->private_dict[3] = ' ';
514
515 parser->root.base = parser->private_dict;
516 parser->root.cursor = parser->private_dict;
517 parser->root.limit = parser->root.cursor + parser->private_len;
518
519 Fail:
520 Exit:
521 return error;
522 }
523
524
525/* END */
return Found
Definition: dirsup.c:1270
#define NULL
Definition: types.h:112
int Fail
Definition: ehthrow.cxx:24
return FT_Err_Ok
Definition: ftbbox.c:511
#define FT_LOCAL_DEF(x)
Definition: ftconfig.h:388
#define FT_ERROR(varformat)
Definition: ftdebug.h:181
#define FT_THROW(e)
Definition: ftdebug.h:213
#define FT_TRACE2(varformat)
Definition: ftdebug.h:159
#define FT_ALLOC(ptr, size)
Definition: ftmemory.h:303
#define FT_FREE(ptr)
Definition: ftmemory.h:329
#define FT_MEM_MOVE(dest, source, count)
Definition: ftmemory.h:231
#define ft_isxdigit(x)
Definition: ftobjs.h:120
#define ft_memcmp
Definition: ftstdlib.h:81
#define ft_memchr
Definition: ftstdlib.h:80
#define FT_FRAME_ENTER(size)
Definition: ftstream.h:512
#define FT_READ_USHORT(var)
Definition: ftstream.h:309
#define FT_STREAM_SEEK(position)
Definition: ftstream.h:489
#define FT_STREAM_POS()
Definition: ftstream.h:486
#define FT_FRAME_EXIT()
Definition: ftstream.h:517
#define FT_STREAM_SKIP(distance)
Definition: ftstream.h:493
#define FT_READ_ULONG_LE(var)
Definition: ftstream.h:318
#define FT_STREAM_READ(buffer, count)
Definition: ftstream.h:497
typedefFT_BEGIN_HEADER struct FT_MemoryRec_ * FT_Memory
Definition: ftsystem.h:66
FT_BEGIN_HEADER typedef unsigned char FT_Bool
Definition: fttypes.h:108
unsigned long FT_ULong
Definition: fttypes.h:253
unsigned char FT_Byte
Definition: fttypes.h:154
int FT_Error
Definition: fttypes.h:300
#define FT_ERR_NEQ(x, e)
Definition: fttypes.h:593
unsigned short FT_UShort
Definition: fttypes.h:209
#define FT_BOOL(x)
Definition: fttypes.h:578
FxCollectionEntry * cur
GLsizeiptr size
Definition: glext.h:5919
GLint limit
Definition: glext.h:10326
GLenum GLsizei len
Definition: glext.h:6722
if(dx< 0)
Definition: linetemp.h:194
#define error(str)
Definition: mkdosfs.c:1605
static char memory[1024 *256]
Definition: process.c:116
#define L(x)
Definition: ntvdm.h:50
static void Exit(void)
Definition: sock.c:1330
Definition: import.c:81
unsigned int error
Definition: inffile.c:97
Definition: parse.h:23
ULARGE_INTEGER pos
Definition: request.c:4380
unsigned int size
Definition: parse.h:27
Definition: ecma_167.h:138
T1_Finalize_Parser(T1_Parser parser)
Definition: t1parse.c:244
T1_New_Parser(T1_Parser parser, FT_Stream stream, FT_Memory memory, PSAux_Service psaux)
Definition: t1parse.c:136
static FT_Error read_pfb_tag(FT_Stream stream, FT_UShort *atag, FT_ULong *asize)
Definition: t1parse.c:70
static FT_Error check_type1_format(FT_Stream stream, const char *header_string, size_t header_length)
Definition: t1parse.c:98
T1_Get_Private_Dict(T1_Parser parser, PSAux_Service psaux)
Definition: t1parse.c:261
FT_BEGIN_HEADER struct T1_ParserRec_ * T1_Parser
#define T1_Skip_Spaces(p)
Definition: t1parse.h:88
#define T1_Skip_PS_Token(p)
Definition: t1parse.h:89